Chain-driven wrench



Oct. 23, 1951 E. T. ABLE ET AL CHAIN DRIVEN WRENCH 2 SHEETS-SHEET 1 Filed May 3, 1948 @e436 j. l

INVENTORS 0W/wn 7. A525 WHL/4R0 /e/AG'EE ,a BY @MKM/? WMM l 1 /l f Oct. 23, 1951 E. T. ABLE ETAL CHAIN DRIVEN WRENCH 2 SI-IEETS--SHEET 2 Filed May 5, 1948 JNVENToRs. EDWARD T A15/ E WILL/:RD KR/EGER Bf @MMM/@W Patented Oct. 23, 1951 CHAIN-DRIVEN WRENCH Edward T. Able and Willard Krieger, Denver, Colo., assignors to B. K. Sweeney Manufacturing Company, Denver, Colo., a corporation of IColorado Application May 3, 194s, serial No. 24,814

Claims. l

This invention relates to chain driven wrenches particularly adapted for working on nuts in the interior of diesel type engines where the nuts are inaccessible or diiiicult to reach by the use of prior art tools, and require great torque to loosen or tighten them.

The main object of the invention is to produce a wrench eflicient'for its intended purposes, wherein the nut engaging socket and power output end of the wrench are removed from the input end and said output end is of minimum size for operation in restricted spaces. The construction is designed so the input end is accessible for actuation of the manually operable lever connected to the input shaft, while the output end is in operative relationship to the work interiorly of the engine housing.

To achieve these and other objects, we have provided a wrench comprising either one or two main units. When two units are used one is a gear or chain driven mechanism including power input means and the other a chain driven transmission"device, adapted to be operatively connected together for transmitting rotary motion to a socket member removably mounted on one end of the transmission device.

An important advantage of the invention lies in the fact that the chain driven transmission devices may be made of different lengths to suit diiierent environments, and the wrench as a whole may be made of one or two units of selected length to suit the environment in which it is to be employed.

Another feature of the invention lies in the Vprovision of back lash controlling means asl'controlling lost motion in the power transmitting means. between the input shaft and the nut engaging socket.

These and other objects and advantages will appear from the following specication.

In the drawings:

Fig. 1 is an elevational side view of a wrench embodying our invention, in operative position relatively to a nut on an engine main bearing; part of the wrench being indicated diagrammatically in dotted lines.

Fig. 2 is a sectional view taken in the horizontal plane indicated by the line 2 2 on Fig. 1, looking downwardly as indicated by the arrows.

Fig. 3 is a longitudinal vertical sectional View of the power input end of the wrench.

Fig. 4 isa sectional View of a detail of construction, namely, the back lash mechanism; the section being taken in the horizontal plane indicated by the line 4-4 of Fig. 3.

Fig. 5 is an elevational side view showing a modified form of wrench embodying our invention, the chain driven unit being partly broken away.

Fig. 6 is a horizontal sectional view of another modification, showing a single unit embodiment of the invention.

Fig. '7 is a vertical sectional View taken in the plane of the dotted line 'I-'I of Fig-6.

Referring to one embodiment of our invention, as shown in Figs. 1 to 4 inclusive, a gear driven mechanism indicated as a whole at I 0, is provided with a manually operable lever I I drivingly engaging the input shaft I2. through gears I3, I4', I5, shaft I1.

The shaft I1 transmits rotary motion to a nut engaging socket I8 through a chain driven transmission device indicated as a whole at I9. The device I9 may be made'as long as desired to span the distance between the shaft I1 of the gear driven member of the wrench and the nut, such as the nut 2U engaged by the socket I8. 2| indicates a fixed end of the bolt on which the nut 20 is mounted. The ready adaptability of the transmission device I9 of our invention to different tasks is an important advantage of our invention.

Said transmission device I9 comprises a housing 22 which is rigidly secured to or integral with an interior frame 23. A bracket 24 projects from one end of the housing 22 to provide anchoring and supporting means for the base of the unit I0. This unit preferably has legs or other straddling means 25 adapted to cooperate with the bracket 24 for mounting the unit II) on th transmission device I9.

Between the ends of the frame 23 and the housing 22 are sprocket wheels 26, 21, respectively, operatively connected by the chain 28 mounted thereon. The sprocket wheel 26 is keyed to a shaft 29 as indicated at 30; said shaft 29 being journalled in the housing 22 and provided I6, drives the output with a square recess in its upper end for drivingly are mounted the shafts, the sprocket wheels and The shaft l2,V

chain. The unit may be made to occupy very limited space between its upper and lower surfaces, whioh is an important advantage when the space above or below the nut to be worked on is restricted. Since the unit I9 may be made as long as desired withoutimpairing the emciency of the `chain drive mechanism, it is possible .to employ a gear driven unit in combination with the chain driven transmission unit, and to mount the manually operable unit l outside .of .the engine housing or in other convenient places easily accessible for the `application of power, without interference by or .danger of `injury .to oil lines, water lines, wiring, yor other parts `of the engine interior adjacent the nuts intended to be worked on by the socket end of :the mechanism.

It will be understood that, in practice, lthe manually operated lever H sometimes cannot be used .to impart continuous .rotary motion to the .input shaft l2, and that the operator :moves :the ,lever through an arc of approxi-mately :12D degrees and then releases the hold to reposition the lever Il ifor a successive operation. 'When it .is .necessary Yto reposition .the manually :o p-

erated input lever for another pull, lost motion .is encountered -in the .chain .and .gear driven mechanisms. This lost motion is .caused bythe elastic stretch of :the chain drive, .or by iplay in the socket, and/or the 'backlash 'in the gear Vdriven mechanism. The lost motion ismultiplied through the Vgear train. In orderzto control this lost .motion a backlash ratchet is 'provided on the 'input pinionaof the geared wrenchrunit to take up any lost motion picked up at each pull.

The back lash controlling means comprises a ratchet 34, ikeyed at .35 toal spindle 3S in a `cylindrical housing 3i positioned in the unit Ihousing |29 vadjacent `the gear I3 on linput shaft 12. The relativepositions of the ratchet '.34 and gear 13 are clearly shown jin Fig. 4. An operating -handle v38 is fixed onthe spindle 3 and is acces- :sible at the top of 'the `unit til as shown in Figs.

.1 and 1'3. A tooth 39 is spring pressed by a spring 4U, in Aan auxiliary housing lll, for engagingone zof the ratchet teeth. When it is desired to hold or control the back lash, the operator turns the handle .38 inthe appropriate direction to move the ratchet into either of the dotted `line positions wherein the 'ratchet tooth 42 or 113 `will be inengagementwith the gear 13 :for the purpose of preventing reverse movement of the power transmitting mechanisms between the input .shaft |12 and the socket i8, when the operator rinterrupts his vmanual rotation of the input shaft I2.

Referring Vnow to the modification shown in Fig. 5, the unit'indicated as a whole at' may be ygear or chain driven and need `not be described in detail. kIt embodies an input .shaft 5i, output kor transmitting shaft 52, and a manually Yopera-ted lever 53 for actuating the vinput `shaft '5L Back lash controlling `means similar to 'that heretofore described is indicated asa whole at 5f.

The unit 50 is designed to cooperate with Aa ychain driven unit IB which is similar to the one Figs. 6 and '7 illustrate that embodiment of the invention in which the wrench consists of a single lunit indicated as a whole at 55, and gear or-c'hain driven `units such as those indicated at i5 and Y5i) 'have been dispensed with. rThe unit 55 comprises two rotatable shafts 56, 51, the shaft 5t being recessed to receive a manually operated shaft 58. The shaft 5l is the output shaft provided with a socket 59 for receiving the shank of a Wrench socket (not shown) similar to the one indicated at i8 in other views. A large sprocket wheel 60 is keyed to the-shaft 56 as indicated at 62, and afsmaller sprocket wheel @G1 is similarly keyed to the shaft El, by a key B2. Said sprocket wheels are operatively connected by an endless chain 63. The parts described are mounted in a housing 6H Aprovided with a frame 65 similar to the parts 122 and 23 -of Figs. l to 4, inclusive, but .shaped Ato -.ac,commodate the different sized .sprocketwheels Vand other mechanism.

In this embodiment the back lash controlling -mechanism .61 Vis mounted adjacent the larger sprocket wheel '60 or input side of the wrench. 'Said mechanism 61 may be of any desired form but as shown it consists of a shaft 68 on which is xedly .mounted a ratchet `or dog 69 which 4en- V,gages one oi the teeth lil of lthe `large sprocket v6B, in the manner .and for Ythe purposes described in connection -with the back ylash controlling means of Figs. 1 to 4, inclusive. The said -mechanism is manually controlled by the handle 1I. A spring pressed tooth Y'lf2 prevents the ratchet or dog V69 from turning except when operated by the handle ll.

From the foregoing `it will vbe Vunderstood that the chain driven unit 55 differs from the unit i9 in Athat the vformer is designed to be actuated by the direct application iof manual :power to the input shaft, :and that due to the diierent sized sprocket wheels on the shafts 55 .and .51, multiplication of power is achieved and transmitted through thechain to the socket shaft 59. Further, said unit -55 includes its own backlash controlling mechanism. Therefore the unit '.55 may be used in certain `environments -Where a single unit is preferred fto the two 'unit fdevices of Figs. 1 to 5, inclusive.

In the two unit embodiments, the .manually operated and power multiplying units I0 and .5.0 may be driven by gears, chain, or other means operatively connecting @the input Vand transmitting shafts for the purpose of ltransmitting rotary motion to the Ychain driven unit.

It will be understood that the extension Tor support 24 on the Ichain -driven unit cooperates with the anchoring means 25 on the units vHl or -50 to support the .latter and anchor it in :operative position on the chain driven unit .Ii9.

Changes may be madein the :form of theparts, in the power transmitting means employed :and in details of constructionwithout departing Vfrom the scope of our invention as .set forth :in the appended claims.

We claim:

1. A Awrench comprising a frame, an input shaft and an output shaft rotatably `mounted-in the frame, means drivingly aconnecting Isaid shafts, means for rotating the input shaft, a gear on the input shaft, a socket operatively connected to the output shaft, and backlash controlling means independent of the imeans drivingly connecting said input and output shafts, and operable independently of the means "for rotating the input shaft, Vsaid backlash vcontrolling ineans comprising a spinc le parallel to the input shaft, a ratchet xed on ysaid spindle vfor operative engagement with lsaid gear on the input shaft, means restraining the `rotation of the ratchet, and manually operable :means for rotating said spindle and ratchet in either direction.

2. A wrench comprising two separable one unit comprising a housing, an input shaft and an output shaft rotatably mounted therein, means drivingly connecting said shafts, means for rotating the input shaft, and backlash controlling means in operative engagement with the input shaft, said backlash controlling means being independent of the means drivingly connecting said input and output shafts, and operable independently of the means for rotating the input shaft, the other unit comprising a frame, a pair of spaced apart rotatable shafts mounted in the frame, a sprocket wheel fixed on each of said shafts, and an endless chain drivingly connecting said sprocket wheels, one of said shafts being adapted for operative connection to the output shaft of the first unit, and a socket on the other of said shafts of the chain driven unit.

3. A wrench comprising a housing, an input shaft and a power output shaft rotatably mounted therein, means drivingly connecting said shafts, means for rotating the input shaft, backlash controlling means in operative engagement with the input shaft, said backlash controlling rreans being independent of the means drivingly connecting said input and output shafts, and operable independently of the means for rotating the input shaft, an elongated frame, a rotatable shaft journalled in each end of the frame, a sprocket wheel fixed on each of said rotatable shafts, an endless chain drivingly connecting said sprocket wheels, one of said shafts being aligned with and operatively connected to the power output shaft, and a socket operatively connected to the other of said rotatable shafts.

4. A chain driven wrench comprising an elongated frame, an input shaft and an output shaft rotatably mounted in opposite ends of the frame, a sprocket wheel xed on each of said shafts, an endless chain drivingly connecting said sprocket wheels, means for rotating the input shaft, a socket operatively connected to the output shaft, and backlash controlling means independent of the means drivingly connecting said input and output shafts, and operable independently of the means for rotating said input shaft,

said backlash controlling means comprising a spindle parallel to the input shaft, a ratchet fixed on said spindle for operative engagement with said sprocket on the input shaft, means restraining the rotation of the ratchet, and manually operable means for rotating said spindle and ratchet in either direction.

5. A wrench comprising a housing, an input shaft and a power output shaft rotatably mounted therein, a gear on the input shaft, means drivingly connecting said shafts, a manually operable removable handle on the input shaft for rotating said shaft, backlash controlling means independent of the means drivingly connecting said input and output shafts, an elongated frame, a rotatable sprocket Wheel shaft journalled in each end of the frame, a sprocket tion of the ratchet, and a manually operable4 handle on the spindle for rotating the spindle and ratchet independently of the rotation of the inl put shaft.

EDWARD T. ABLE. WILLARD KRIEGER.

REFERENCES CITED The followingf references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 891,615 Geiger et al June 23, 1908 1,356,555 Oringderff Oct. 26, 1920 1,494,200 Waters May 13, 1924 2,341,775 Hawk Feb. 15, 1944 2,353,642 Buice July 18, 1944 2,379,878 Bronander July 10, 1945 2,436,650 Killmer Feb. 24, 1948 2,460,671 Benedick Feb. 1, 1949 2,466,456 Lybyer Apr. 5, 1949 2,482,387 Veneman Sept. 20, 1949 2,539,861 Robinson Jan. 30, 1951 FOREIGN PATENTS Number Country Date 642,558 France May 6, 1928 

